Cellular Phones use 824-MHz to 894-Cellular Phones use 824-MHz to 894-MHz frequency bands. Some obstaclesMHz frequency bands. Some obstaclesto this in the near future are missingto this in the near future are missingroaming and authentication features inroaming and authentication features inSIM cards and radius, the narrowness of SIM cards and radius, the narrowness of the available spectrum and the limitedthe available spectrum and the limitedrange.range.ie,Wi-Fi will directly compete againstie,Wi-Fi will directly compete againstcellular.cellular.